Off-Season Stock Car Maintenance

We continually speak of setup or engine tuning that can make the difference in how well your car measures up to the competition. Each subject is presented as the final hurdle that may make the difference to produce that first win or championship, which we believe is possible. The work you do to get the right setup and engine combination, as well as the skill developed by the driver to run up front, can all go to somewhere in a hand basket if something should break.

Maintenance is not considered a performance topic, and taking care of each part on a regular basis is not even on many racers' radar screens most of the time. The first indication of a maintenance problem usually comes when we drop a valve while leading a race, or when the right-front, lower ball joint gives up the ghost and we have a serious discussion with the Turn 4 wall.

All racers have a strong desire to win. We put untold effort into adjusting the setup, tuning the engine, preparing the tires, and coaching the driver to achieve that thrill of the checkered flag. In short, we may get too busy in that pursuit to bother with maintenance. Well, at the end of a season, there's no excuse for not tearing the car down and doing a much needed complete maintenance job on all of the components.

Here are some suggestions on maintenance that relate to the most common failures associated with stock car racing. We looked over some team maintenance sheets and thought back on our own racing experiences and failures to present what we consider the most important items to think about not only at year's end, but throughout the season.

These failures can end your hopes in a hurry.

1. Ball joint failure - The ball joint shaft can break if it has been stressed in the past. A slightly bent ball joint shaft may look OK and possibly be used again, but the chances are good that the metal has been stressed. There could be a hidden crack that only shows up when X-rayed or when it fails. These are cheap items in the grand scheme of things, so buy new ones after they have been in a serious confrontation.

2. Heim joint failure - Inspect all of your Heim joints often. Never use aluminum Heim joints where there is a high level of stress and force. The uses to avoid are: Third link in a three-link rear suspension (under a high level of tension when the car is accelerating); lower control arm and strut arm pivots; Panhard/J-bar end pivot points (There is a high degree of tension on the track bar); and any steering component pivot point (even a light hit can cause a steering failure here). The weight saved by using aluminum instead of steel is not worth the risk of failure of any of these critical components.

3. Shocks and mounting point stress cracks - We often see stress cracks in the area where the shock mounts are welded to the frame. These are high-stress areas. Failure here is a high possibility because of the constant movement of rebound and compression experienced by the mount. Loss of a shock at any corner can ruin a good day.

When time allows, have all of your shocks inspected, dynoed, and rebuilt by an experienced shock technician. This could be a crewmember who knows what he is doing, or a professional who does it for a living. The pro route costs much less than buying new ones. You can rest assured that your handling problems will not include an errant shock rate.

4. Wheel parts - Normally, we would think nothing of putting off wheel bearing maintenance because we don't often have problems in that area. Occasionally, however, the high heat generated by the brakes migrates down through the hub to the bearings and cooks the bearing lubricant. The top teams make sure they inspect and regrease the wheel bearings several times within a season.

While you are at the wheel, check the stud threads for excess wear and replace them if the lug nut is too loose on the stud. Inspect those wheels while you're at it. Again, look for stress cracks and bent rims.